The adiabatic expansion nozzle (U.S. Pat. No. 6,116,049 issued Sep. 12, 2000 to DOT, inventor Robert Filipczak) demonstrated superior firefighting ability. Later designs, submitted after the patent was issued found that a replacement nozzle could be made for the ordinary discharge horn on a hand-held, 5-pound carbon dioxide fire extinguisher. Off-the-shelf fire extinguishers made by several companies were retrofitted with a suitably sized adiabatic expansion nozzle, by unscrewing the ⅛ NPT thread on the existing discharge horn and screwing in the adiabatic expansion nozzle. The nozzle worked well but was not very robust. Solder joints failed in some versions of the nozzle and residual dry ice developed inside and could lead to clogging. While the US Government tried to license the idea to private companies, none were willing to take on what was, in essence, a research project or go through the licensing procedure. The fluorocarbon (HFC-23) version worked in the FAA hidden fire scenario, but was not considered a viable replacement agent because high levels of hydrofluoric acid were produced, dangerous to anyone not wearing a self-contained breathing apparatus (SCUBA). Some of the FAA research efforts are contained in an internal publication, “Development and Performance of an Adiabatic Expansion Nozzle for Improved Fire Extinguishers” DOT/FAA/AR-TN01/60. The project has been dormant since the retirement of the inventor from DOT in 2006. All subsequent research, design, and reduction to practice has not involved DOT support or moneys.